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bioRxiv · 10.1101/2022.12.08.519702

Incidence, antifungal resistance properties, and virulence traits of candida species isolated from HIV/AIDS Patients from the hospital system in Kenya.

Miruka, H. N.·Omori, E.·Musyoki, S.·Awuor, S.
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Abstract

Candidiasis is the most common fungal infection in hospitalized patients with acquired immune deficiency syndrome resulting to morbidity and mortality. This study aimed at characterizing, incidence, susceptibility, resistance genes, antibiofilm activity, and virulence traits of Candida species isolated from HIV-Infected patients. One hundred and eighty-one samples were collected and cultured on Sabouraud Dextrose Agar, biochemical tests and confirmed using automated Vitek-2 (R) Compact bioMerieux followed by susceptibility tests. were done by use of various conventional antifungals against the isolates using standard procedures. Virulence factors, biofilm formations and resistance genes of Candida strains were determined. Out of the 181 samples, 46 were identified as Candida spp., 20 C. albicans (43.5%), 6 C. tropicalis (13.0%), 8 C. krusei (17.4%), 4 C. glabrata (8.7%), 3 C. famata (6.5%), 3 C. parapsilosis (6.5%), and 2 C. guilliermondii (4.3%). All the Candida albicans isolated were both Gram positive and Germ test tube test positive. Eighteen (90%) of the isolates were susceptible to Clotrimazole at a concentration of 5 g/mL - 10g/mL followed by 17 (85%) isolates to Panosoconazole at a concentration of 0.002 g/mL - 5g/mL. Eight (40.0 %) of the Candida albicans isolates possessed the gene (cdr1) that was observed at 286 bp. Virulence enzymes was determined in which 100% produced Haemolysin, followed by proteinase (75.0%), phospholipase (50%), coagulase at (50%) and lastly capsulase (25.0%). Fluconazole and Clotrimazole did not inhibit growth of C. albicans at high concentrations but from our study, it was deduced that they inhibit biofilm formation at lower concentrations. C. albicans isolates were resistant to multiple antifungal including those commonly used in the management on HIV/AIDs patient. This attributed to resistant genes and produced various virulence factors that were found to be present in the isolates. Therefore, there is a need to carry out regular surveillance on antifungal drug resistance.

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Miruka, H. N., Omori, E., Musyoki, S., Awuor, S.. 2022-12-09. Incidence, antifungal resistance properties, and virulence traits of candida species isolated from HIV/AIDS Patients from the hospital system in Kenya.. https://doi.org/10.1101/2022.12.08.519702

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